Early on, doctors told Kyle Runyon’s parents their son wouldn’t be able to play sports.

Runyon played anyway, improving his skills as each year passed. Now a senior at Coronado High, Runyon has committed to play lacrosse for Notre Dame.

Sixteen years ago, that didn’t seem possible.

Runyon was diagnosed with retinoblastoma, a rare type of eye cancer, when he was 18 months old. The cancer was contained to his left eye, which was removed.

Up until he was 4 years old, Runyon was seen four times a year to make sure the cancer hadn’t spread to his other eye. He still gets a checkup every year.

“It would’ve been great … if he had been a bookworm or taken up golf,” said Sue Runyon, his mother. “But he didn’t. From the day he stepped on the soccer field as a 5-year-old he was usually the best kid on the team. He’s been a natural athlete his whole life.”

Though doctors said Runyon wouldn’t be able to play baseball or any other sport because of his lack of depth perception, that didn’t stop him.

“The coach put him in center field and he was catching fly balls with blue skies behind him,” his mother said. “So everything they said he couldn’t do he was doing. It hasn’t hindered him. It’s just he doesn’t have an extra (eye) like everybody else does.”

Runyon was required to wear protective goggles when playing baseball and because of that he said he didn’t stick with the sport.

Instead, he continued to excel in soccer and lacrosse, which he began playing in the fifth grade.

Runyon was sidelined most of his junior year after discovering he had stress fractures in two vertebrae. He wasn’t allowed to do much of anything for five months, missing the entire soccer season and part of lacrosse.

Runyon returned to play soccer his senior season and added a second San Diego Section title to his résumé this winter as Coronado (24-1-1) beat Francis Parker 1-0 in the championship game. He was named All-Central League after leading the Islanders with 17 goals and 10 assists.

Coronado soccer coach Brian Hiatt, who has worked with Runyon since he was 8, said his visual impairment has never been an issue.

“Never made an excuse about it,” Hiatt said. “Never talked about it.”

Hiatt said opposing coaches and referees are surprised when they learn of the challenge Runyon has overcome.

“He’s basically our strongest forward. He’s extremely creative with the ball,” Hiatt said. “If you wear No. 10 in soccer, you’re the best player on the field.”

Runyon has swapped his No. 10 soccer jersey for a lacrosse uniform this spring. The All-American is vying for his second section title after helping Coronado earn a championship in 2009.

Runyon was recruited by several Division I lacrosse programs but elected to play at Notre Dame, noting the academics and the presence of the Fighting Irish lacrosse team in last year’s NCAA finals.

“And their football and basketball teams — I’ve always wanted to go to a school with good athletics,” Runyon said.

Coronado lacrosse coach Alex Cade has mentored Runyon since he was in the sixth grade.

“His tremendous work ethic combined with his lacrosse IQ will serve him well at the next level,” Cade said. “Kyle is an extremely dynamic player on the lacrosse field with the ability to hurt you from multiple positions and in multiple ways.”

Runyon, a first-team all-section choice in lacrosse, said the challenge he’s faced has never interfered with his ability to play sports.

His mother remembers that as a young soccer player he never wanted to be singled out for what he didn’t have.

“This has been how he has approached sports ever since,” she said.

Though her son shows a reluctance to draw attention to himself, he does have a message for anyone who has something to overcome:

“I think I could be a good example of why you shouldn’t let anything stop you from doing what you want to do just because you think that there’s something that’s holding you back.”